Periodic Table - Elemental developments
Elemental developments
All matter on Earth is made up of elements. There are only a finite number of natural elements, although others are synthesized or manufactured by people. (As of 2003, there were 110 officially named elements, plus several more created in laboratories awaiting names.) The periodic table leaves spaces for unknown elements still to be discovered.
The desire to categorize elements goes back to the fifth century B.C. when ancient Greeks theorized that all matter falls under four elements: Earth, air, fire, and water. In 1789 French chemist Antoine Lavoisier (1743–1794) published the definition and first set of thirty-three chemical elements. Lavoisier grouped them into four categories on the basis of their chemical properties: gases, nonmetals, metals, and earths.
As more elements were discovered, many scientists worked on classifying them. The turning point came when Russian chemist Dmitri...
[The entire page is 453 words long]
Join eNotes
Over 3,500 study guides, question and answer forums, literature criticism, reference content, and much more!
Navigate
